When the length of a rectangle is increased by 20% and the width increased by 10%, by what percent is the area increased?

Say L (the length) is 10, and W (the width) is also 10.

 

The area of this rectangle would be 10 * 10 = 100 square units.

 

With the newer figures, we get the sides to be L = 12 and W = 11. The area of this is 12 * 11 = 132.

 

132 is a 32% increase from 100 :D

L x W = A

1.2 L x 1.1  W  = 1.32 L X W         1.32  corresponds to increase 1.32 times original A....or    32% increase